Why do they put empty hennessy bottles at makeshift memorials?

I was visiting my friend while walking through the streets of Chicago... And I spotted a make shift memorial over a person who was shot dead at that spot. There were Jesus candles and teddy bears. However there was a row of empty hennessy bottles lined up. I find it disrespectful to have an alcoholic beverage represented for someone who was under 18 and got shot.|||yeah its tacky. it's like memoralizing someone with garbage